The surface of Saturn’s huge moon Titan has the consistency of soft, wet sand with a fragile crust on top, a new analysis of a nearly eight-year-old space probe landing suggests.
Image: This image is an artist’s impression of the descent and landing sequence followed by ESA’s Huygens probe that landed on Titan. The Jan. 14, 2005 landing was the culmination of a 22-year process of planning, organizing and cooperation between ESA and NASA. Credit: NASA/JPL/ESA
Researchers reconstructed the European Space Agency’s Huygens probe landing on Titan, which occurred in January 2005. They determined that Huygens bounced, slid and wobbled to a stop 10 seconds after first making contact with the moon.
The study — which incorporated data from Huygens’ instruments and results from computer simulations and a drop test with a model — found that the 400-pound (181-kilogram) probe made a dent 4.7 inches deep (12 centimeters) upon touching down.
“A spike in the acceleration data suggests that during the first wobble, the probe likely encountered a pebble protruding by around an inch from the surface of Titan, and may have even pushed it into the ground, suggesting that the surface had a consistency of soft, damp sand,” study lead author Stefan Schröder, of the Max Planck Institute for Solar System Research in Germany, said in a statement.
This conclusion is broadly consistent with previous studies of the landing, which determined that Titan’s surface is likely quite soft. But the new analysis suggests that a sort of crust lies on top of the soft stuff.
“It is like snow that has been frozen on top,” said co-author Erich Karkoschka of the University of Arizona. “If you walk carefully, you can walk as on a solid surface, but if you step on the snow a little too hard, you break in very deeply.”
The fact that Huygens bounced and wobbled rather than simply “splatted” suggests that the moon’s surface was dry when it touched down, researchers said. This interpretation is bolstered by the dusty cloud the probe seems to have kicked up.
I know I’ve written my own posts on Cassini and the Huygens probe before, but this shit bears repeating: we landed a probe on motherfucking Titan, guys. And got pictures and data back. This is a thing we can do.